Expansible proportional rule



FIG. 1 is a top plan view of an expansible proportional rule showing my new design;

FIG. 2 is a front edge elevational view thereof, the raised portions of the rear edge having been omitted for ease of illustration;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a rear edge elevational view thereof, the raised portions of the front edge having been omitted for ease of illustration;

FIG. 5 is a left end elevational view thereof;

FIG. 6 is a right end elevational view thereof;

FIG. 7 is a top plan view of another embodiment of my new design of FIGS. 1-6;

FIG. 8 is a front edge elevational view thereof, the raised portions of the front edge having been omitted for ease of illustration;

FIG. 9 is a bottom plan view thereof;

FIG. 10 is a left end elevational view thereof;

FIG. 11 is right end elevational view thereof;

FIG. 12 is a top plan view of a third embodiment of my new design of FIGS. 1-6, the bottom plan view being identical to FIG. 3;

FIG. 13 is a typical front or rear edge elevational view of the third and fourth embodiments of the design;

FIG. 14 is a typical left or right end elevational view of the third and fourth embodiments of the design;

FIG. 15 is a top plan view of a fourth embodiment of my new design of FIGS. 1-6, the bottom plan view being flat, plain and unornamented.

FIG. 3, besides being an illustration of the reverse face of the embodiment of the Rule of FIG. 1, is also a true visual representation of the reverse face of the Rule embodiment of FIG. 12; and

The reverse face of the embodiment of FIG. 15, which is not shown, is blank (i.e., without graduation scales). 

The ornamental design for an expansible proportional rule, as shown and described. 